### Write a C Program to Compute the LCM and HCF of Two Numbers by using While Statement

HCF:
• HCF Stands For Higest Common Factor.
• HCF is also Known as GCD (Greatest Common Divisor).
• HCF of Two Number is defined as the Largest Number that Divides Both Numbers Completely with Remainder Zero.
LCM:
• LCM Stands For Lowest Common Multiple.
• LCM of two Numbers Defined as the Smallest Number that is Multiple of both Numbers.
Statement of C Program: Find The LCM and HCF of Two Numbers :

#include<stdio.h>
#include<conio.h>

void main()
{
int num1 , num2 , lcm , gcd , remainder , numerator , denominator ;
clrscr();

printf( "Enter two numbers\n");
scanf(" %d%d " , &num1 , &num2 );
if (num1 > num2)
{
numerator=num1;
denominator=num2;
}
else
{
numerator = num2 ;
denominator = num1 ;
}

remainder = num1 % num2;
while ( remainder != 0)
{
numerator = denominator;
denominator = remainder;
remainder = numerator % denominator;
}
gcd = denominator;
lcm = (num1 * num2 ) / gcd;

printf("GCD of %d and %d =%d\n" , num1, num2, gcd);
printf(" LCM of %d and %d= %d\n" , num1, num2, lcm);
getch();
}

Output:
Enter two numbers
5
15
GCD of 5 and 15 = 5
LCM of 5 and 15 = 15

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1. Chosen participants will receive financial support to attend WLA conferences,
dissertation topics coming up

2. hey dear there is a bug in the program :
just type num1 a smaller value then num 2 ...
the program will not generate desired output.. here is the simple modification :

int main()
{
int num1 , num2 , lcm , gcd , remainder , numerator , denominator;

printf( "Enter two numbers\n");
scanf("%d%d" , &num1 , &num2 );
if (num1 > num2)
{
numerator=num1;
denominator=num2;
remainder = num1 % num2;//now at correct place :)
}
else
{
numerator=num2;
denominator=num1;
remainder = num2 % num1;// this was missing :)
}
while ( remainder != 0)
{
numerator = denominator;
denominator = remainder;
remainder = numerator % denominator;
}
gcd = denominator;
lcm = (num1 * num2 ) / gcd;

printf("GCD of %d and %d =%d\n" , num1, num2, gcd);
printf(" LCM of %d and %d= %d\n" , num1, num2, lcm);
getch();
return 0;
}

3. http://www.compprog.com/2013/07/find-highest-common-factor.html This will describe your question better

4. C++ Program to Find HCF of two numbers

To find the HCF or GCD of two or more numbers, make prime factors of the numbers and choose the common prime factors. Then the take the highest common factor this highest common factor is HCF of number.